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1、材料科学基础FundamentalofMaterials Lessontwenty two 5 12InteractionbetweenDislocationandPointDefect Bycottrellatmospheremodel wecanexplainthesharpyieldingphenomenon CottrellAtmosphereStrainaging PointdefectCottrellAtmosphere strainaging BCC 5 13Multiplicationofdislocations What smultiplicationandwhyisitne
2、eded Keypointsofthemechanismsofthemultiplication Thedislocationdoesnotlieentirelyonthesameslipplane Partofthedislocationsegmentscannotmoveforeitherofthefollowingreasons NoappliedstressTheplaneonwhichthesegmentwouldmoveisnotallowedcrystallographically Thereisstrongobstaclesaroundthesegment Frank ReadmechanismorF Rsource F Rmechanism L shapeddislocation F Rsource Whendislocationisinquasi staticequilibrium Whendislocationwillspontaneouslyslip ExamplesandDiscussions Exercise Thankyou 22